General descriptive studies (00350): Following decades of rising breast cancer incidence in the U.S. there were abrupt declines circa 2000 that stabilized during 2003-2004. The fall in breast cancer rates occurred mostly among older women with ER positive cancers. Much less attention was given to falling ER negative cancer rates. Circa 1990 breast cancer mortality rates began to fall with an estimated annual percentage change of approximately 2% per year. The fall in breast cancer mortality rates have generally been attributed to the combined effect of improvements in screening mammography and/or breast cancer treatment. However, declining breast cancer mortality may not simply reflect better screening and treatment, but also might be related to changing breast cancer biology due to falling ER negative incidence rates. Breast cancer is a heterogeneous disease, divisible into a variable number of clinical subtypes. A fundamental question is how many etiological classes underlie the clinical spectrum of breast cancer? We reviewed the evidence for breast cancer etiological heterogeneity. Results showed a bimodal age distribution at diagnosis with peak frequencies near ages 50 and 70 years for important tumor features, consistent with a two-component mixture model and compatible with a hierarchal view of breast cancers arising from two main cell types of origin. There are limited data regarding the burden of breast cancer subtypes among Hispanic women. We, therefore, assessed the distribution and prognosis of the molecular subtypes among Hispanics using California Cancer Registry data from 2005-2010. Breast cancer subtypes were defined as hormone receptor (HR) and HER2 receptor: HR+/HER2-, HR+/HER2+, HR-/HER2+, and HR-/HER2- (triple negative). Among 16,380 Hispanic breast cancer patients, HR+/HER- subtype was most common, followed by triple negative, HR+/HER2+ and HR-/HER2+. Previous reports suggested that female breast cancer is associated with earlier ages at onset among Asian than Western populations. However, most studies utilized cross-sectional analysis that may be confounded by calendar-period and birth-cohort effects. We, therefore, considered a more longitudinal approach adjusted for calendar period changes and conditioned upon birth-cohorts. Invasive female breast cancer case and population data (1988-2009) were obtained from cancer registries in Asia and the United States. Similar shapes in longitudinal curves along with converging IRRs from one generation to the next suggested that the natural history of invasive breast cancer was more similar among Asian and Western populations than might be expected from a solely cross-sectional analysis. Indeed, estimates for the most recent cohorts in some Asian countries show even later ages at onset than in the US. Cancer risk after blood transfusion was evaluated in a US population-based case-control study using 552,951 elderly cases identified from cancer registries and 100,000 frequency-matched controls. Transfusions received 0 to 12, 13 to 30, and 31 to 48 months before cancer diagnosis or selection dates were identified using Medicare claims. Transfusions received 0 to 12 months before cancer diagnosis and/or selection were associated with significantly elevated risk of cancer overall (odds ratio [OR], 2.05; 95% CI, 1.95-2.16) and cancer of the stomach; cancer of the colon; cancer of the liver, kidney, renal pelvis, and/or ureter; lymphoma; myeloma; and leukemia. No significant associations for cancer overall were observed for the two earlier intervals. No site was associated with transfusions received 13 to 30 or 31 to 48 months before diagnosis and/or selection. Nonetheless, overall cancer risk increased with the number of transfused periods (p-trend 0.0001). The increased risk of overall cancer and specific sites 0 to 12 months after blood transfusion is likely due to reverse causation, that is, incipient cancers or cancer precursors causing anemia. Transmission of cancer is a life-threatening complication of transplantation. Monitoring transplantation practice requires complete recording of donor cancers. The US Scientific Registry of Transplant Recipients (SRTR) captures cancers in deceased donors (beginning in 1994) and living donors (2004). We linked the SRTR (52 599 donors, 110 762 transplants) with state cancer registries. Cancer registries identified cancers in 519 donors: 373 deceased donors (0.9%) and 146 living donors (1.2%). Among deceased donors, 50.7% of cancers were brain tumors. Among living donors, 54.0% were diagnosed after donation; most were cancers common in the general population (e.g. breast, prostate). There were 1063 deceased donors with cancer diagnosed in the SRTR or cancer registry, and the SRTR lacked a cancer diagnosis for 107 (10.1%) of these. There were 103 living donors with cancer before or at donation, diagnosed in the SRTR or cancer registry, and the SRTR did not have a cancer diagnosis for 43 (41.7%) of these. The SRTR does not record cancers after donation in living donors and so missed 81 cancers documented in cancer registries. In conclusion, donor cancers are uncommon, but lack of documentation of some cases highlights a need for improved ascertainment and reporting by organ procurement organizations and transplant programs. Solid organ transplantation recipients have elevated cancer incidence. The cumulative incidence of 6 preventable or screen-detectable cancers after transplantation was estimated using population-based data on 164,156 US transplantation recipients. High-risk subgroups are identified that may benefit from targeted screening or prevention, including thoracic organ recipients at the extremes of age for non-Hodgkin lymphoma, older thoracic organ recipients for lung cancer, and kidney recipients aged 35 years for kidney cancer In a large US population-based study, the authors demonstrate that transplant recipients have an elevated risk for plasma cell neoplasms and document several risk factors for this type of malignancy, including Epstein Barr virus infection, recipient age, and the presence of primary biliary cirrhosis. The classification of lung cancers by histologic type was updated and the new refined categories were used to assess the US incidence patterns. Temporal trends were found to vary by gender, type, racial/ethnic group, and age, reflecting historical cigarette smoking rates, duration, cessation, cigarette composition, and exposure to other carcinogens. The new categories and SEER data are being used in the upcoming 4th edition of the WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart. Testicular germ cell tumors are the most commonly occurring cancers among US men ages 15-44 years, and rates were found to be highest among non-Hispanics, followed by American Indian/Alaska Natives, Hispanic whites, Asian/Pacific Islanders, and blacks. Retinoblastoma incidence rates were found to be decreasing significantly since 1992 among those younger than 1 year and since 1998 among those with bilateral disease. In addition, consistent with other cancers, an excess of retinoblastoma diagnosed in boys suggests a potential effect of sex on cancer origin. The incidence of extranodal marginal zone lymphoma exceeds that of nodal disease, and the most common extranodal sites are the stomach, spleen, and eye/adnexa. The age-specific patterns increased steeply at young ages and less prominently after mid-life for several sites. The temporal trends, gender and racial/ethnic disparities varied by site, supporting the contention that marginal zone lymphoma is characterized by etiological heterogeneity across sites and that susceptibility is probably influenced by intrinsic characteristics and environmental exposures.